Multi-line mobile service with dynamic MSISDN association

ABSTRACT

Methods and computing systems for dynamic MSISDN association are described. A network device receives a location update message from a mobile network switch. The location update message indicates that a mobile device is registered with the mobile network switch. The location update message includes an international mobile subscriber identity (IMSI) associated with the mobile device. The network device determines, based at least on the IMSI, a plurality of MSISDNs associated with the mobile device, including a first MSISDN that is enabled for calling and a second MSISDN that is not enabled for calling. The network device transmits, in response to the location update message, subscriber data to a database associated with the mobile network switch, which associates the IMSI with the first MSISDN.

BACKGROUND

A GSM phone includes a subscriber identity module (SIM) card, which hasan international mobile subscriber identity (IMSI) stored thereon. AnIMSI is a unique 64-bit number. Within a GSM network, the IMSI isassociated with the MSISDN, sometimes referred to as the “Mobile StationInternational Subscriber Directory Number,” or colloquially as thetelephone number. The MSISDN is a unique number that identifies asubscription on the GSM network and is also the number that can be usedto place a call to the GSM phone. The MSISDN is not necessarily storedon the SIM card or the phone, and the MSISDN is not permanentlyassociated with the IMSI. The MSISDN may change if the subscriptionchanges, for example.

In a typical GSM phone registration situation, the phone registers witha mobile switching center (MSC), and a visitor location register (VLR)is updated. After the registration authentication procedure iscompleted, the MSC/VLR sends a location update mobile application part(MAP) message to a home location register (HLR) with the IMSI of thephone that is registered. The HLR replies back with a MAP insertsubscriber (ISD) message that provides subscription information to theMSC/VLR including the MSISDN.

When a call comes into the GSM network, it passes through a gateway MSC,which sends out a send routing information (SRI) message to the HLR thatthe phone is registered with. The HLR sends a provide roaming number(PRN) message to the MSC where the user device is registered, the MSCsends back a mobile station roaming number (MSRN), and the HLR sends theMSRN as a response to the SRI. The MSRN is a temporary number that theMSC/VLR maps to the MSISDN. The gateway MSC routes the call to the MSCthat the called party is registered on using the MSRN.

To enable multi-line services—such as two phone numbers for one mobilephone—a dual SIM phone may be used. The SIM stores two IMSIs, andregisters one or both of them with the MSC/VLR, depending on the mode ofthe phone.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is set forth with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different figures indicates similaror identical items or features.

FIG. 1 illustrates a network and a process for multi-line mobile deviceregistration with dynamic MSISDN association.

FIG. 2 illustrates a network and a process for dynamic update of MSISDNassociation.

FIG. 3 illustrates a network for incoming call handling for call to acurrently enabled MSISDN.

FIG. 4 illustrates a network and a process for incoming call handlingwith dynamic update of MSISDN association.

FIG. 5 illustrates an example network device configured to performdynamic MSISDN association.

DETAILED DESCRIPTION

In embodiments of the present disclosure, a proxy is introduced into atelecommunications network, such as a global system for mobilecommunications (GSM) network, to enable multi-line service (multiplephone numbers and subscriptions) to be associated with a single IMSI anda single mobile device. The proxy is associated with IMSIs of mobiledevices that have multi-line service. A database associated with theproxy houses the user associations, including the pairings of IMSIs andMSISDNs to a single user or a single mobile device, and indicates whichMSISDNs are currently active (e.g., which MSISDNs the IMSI is authorizedto use) and which are currently enabled for calling (or “in focus”) onthe mobile device. Some component of the phone, either an application oran operating system component, enables the selection of a particularMSISDN to be enabled. In other words, the user or application can selecta telephone number for outbound calls.

FIG. 1 illustrates a network 100 and a process for multi-line mobiledevice registration with dynamic MSISDN association. User equipment (UE)102 at some point wirelessly connects to and registers with a MSC/VLR104. During registration the UE 102 provides its IMSI to the MSC/VLR104. In a conventional registration, the MSC/VLR sends a MAP locationupdate (LUP) message to an HLR 106 and the HLR 106 responds with a MAPISD message providing the MSISDN and other subscription information. TheVLR is a database associated with the MSC. The VLR and the MSC may behoused together, or separately. In embodiments shown herein, the MSC andthe VLR are shown together for the sake of illustration only.

The UE 102 is associated with two or more MSISDNs on the network 100. Atsome point, a Multiline Services Database (MDB) 110 may be updated toreflect that a particular MSISDN associated with the UE 102 is enabledfor calling (this is shown in FIG. 1 with an arrow labeled with acircled “1”). Various mechanisms may be employed to change the MSISDNthat is enabled for calling. The update may be based on an applicationprogramming interface (API) call placed from the UE 102 to the MDB 110or to the proxy 108, or to another device. The update may be based onplacement of an inbound call, as discussed in more detail in FIG. 4. Theupdate may occur for some other reason, such as based on a time-of-day,day-of-week setting, or based on some other setting. The MDB 110 isconfigured to store information associating a plurality of MSISDNs witha UE and/or with a user, such as the UE 102. The database is furtherconfigured to store an indication of a MSISDN of the plurality ofMSISDNs that is currently enabled for calling.

In the example shown in FIG. 1, MSISDN1 is enabled for calling, MSISDN2is active but not enabled for calling, and MSISDN3 is inactive and alsonot enabled for calling. Active as used herein means that thesubscription and associated MSISDN is currently available for inboundand outbound calls, and can be enabled either through user action orautomatically in some circumstances, such as based on an incoming callto that MSISDN. An incoming phone call placed to an active but notenabled MSISDN causes the MSISDN to become enabled and the call isplaced to the UE 102 (this is shown in more detail in FIG. 4). A phonecall placed to an inactive MSISDN—such as MSISDN3—will not cause theinactive MSISDN to become enabled for calling, and the call will not beplaced to the UE 102. The same or similar is true for other mobile GSMservices, such as short message service (SMS). A voice call or SMSmessage placed or sent from the UE 102 will be placed to or sent fromthe MSISDN that is currently both active and enabled.

In the example illustrated in FIG. 1, database portion 112 shows thatIMSI1—which is the IMSI stored on a SIM 114 within the UE 102—isassociated with three IMSIs (IMSI1, IMSI2, and IMSI3) and three MSISDNs(MSISDN1, MSISDN2, and MSISDN3).

In embodiments of the present disclosure, when the UE 102 registers withthe MSC/VLR 104, the MSC/VLR 104 sends a MAP LUP message to a proxy 108to register the IMSI with the HLR (shown in FIG. 1 with a circled “2”).In embodiments, the proxy 108 emulates the HLR 106 when communicatingwith the MSC/VLR 104. Emulation of the HLR 106 means in part that theproxy 108 is configured to engage in various protocol communications asif it were an HLR according to relevant standards, such as the relevantGSM standards.

The proxy 108 determines, based at least on the IMSI in the MAP LUPmessage, a plurality of MSISDNs associated with the UE 102, includingfor example a first MSISDN that is enabled for calling and a secondMSISDN that is not enabled for calling. In the example shown in FIG. 1,the proxy 108 performs a look-up to the MDB 110 to determine the MSISDNthat is currently enabled and also to determine all active MSISDNsassociated with the IMSI (shown in FIG. 1 with a circled “3”). The MDB110 provides the MSISDN/IMSI pairings associated with the UE 102 andIMSI1, as well as an indication of the MSISDN that is enabled (shown inFIG. 1 with a circled “4”).

The proxy 108 sends MAP LUP messages to the HLR 106 for all activeMSISDNs associated with UE 102 (shown in FIG. 1 with a circled “5”). Inthe example shown in FIG. 1, there are two active MSISDNs—MSISDN1 andMSISDN2—associated with IMS1 and UE 102 in the MDB 110. Thus, the proxy108 sends two MAP LUP messages to the HLR 106, one for IMSI1 and anotherIMSI2. By doing so, the HLR 106 registers both IMSI1 and IMSI2 with theproxy 108. The proxy 108 emulates a MSC/VLR in this communication withthe HLR 106, thereby causing the HLR 106 to “think” that the proxy 108is a MSC/VLR that has registered both IMSI1 and IMSI2. Emulation of theMSC/VLR 104 means in part that the proxy 108 is configured to engage invarious protocol communications as if it were an MSC/VLR according torelevant standards, such as the relevant GSM standards. Although the SIM114 of the UE 102 only has a single IMSI—IMSI1—stored thereon, multipleISIs are stored in the MDB 110, and transmitted to the HLR 106 in theMAP LUP messages in part to conform to the relevant standards which mayprovide that there is a single IMSI/MSISDN pairing, and also so that theHLR 106 need not have additional logic that allows it to handle multipleMSISDNs paired with a single IMSI.

The HLR 106 responds to the MAP LUP messages with MAP ISD messages forall MSIDN/IMSI pairs associated with the UE 102 (shown with a circled“6”) in FIG. 1). The MAP ISD messages include subscriber data for thoseMSISDNs, including the MSISDNs themselves. The proxy 108 determines theMSISDN that is currently enabled (or “in focus”) on the UE 102. Theproxy 108 emulates an HLR in its communications with the MSC/VLR 104.The proxy 108 transmits subscriber data associated with the MSISDN thatis currently enabled for calling, and may not transmit subscriber dataassociated with a MSISDN that is not currently enabled. For example, theproxy 108 transmits a MAP ISD message for the MSISDN that is currentlyenabled for calling (shown in FIG. 1 with a circled “7”). In this way,the proxy 108 causes the MSC/VLR 104 to associate that subscriberinformation in the MAP ISD message (including the currently enabledMSISDN) with the IMSI stored in the UE 102 (in this example, IMSI1 isassociated with MSISDN1).

Any outbound call from that UE 102 is placed using the MSISDN that iscurrently enabled, and associated with the IMSI on the MSC/VLR 104.While MSISDN1 is enabled, and associated with IMSI1 in the MSC/VLR 104,any call detail records produced for billing purposes would be producedfor MSISDN1 and the associated subscription. Were IMSI2 enabled—insteadof IMSI1—proxy 108 would transmit the MAP ISD message for MSISDN2, andthe MSC/VLR 104 would associate IMSI1 with MSISDN2. Any call detailrecords produced for billing purposes would be produced for MSISDN2.

The network 100 may support one or more of Global System for MobileCommunications (GSM) protocols or standards. The UE 102 may be anynumber of wireless devices, such as mobile telephone handsets, tabletcomputers, wireless modems, personal computers, laptops, and so forth.The network 100 may provide to the wireless end-user devices one or moreof voice service, video service, data service, messaging service (e.g.,short messaging service (SMS), multimedia messaging service (MMS)), orother wireless services.

FIG. 2 illustrates a network 100 and a process for dynamic update ofMSISDN association. As noted above, the UE 102 may change the MSISDNthat is enabled for calling in various ways, such as by calling an APIto the MDB 110, the proxy 108, or to some other device, or in some otherway. In the example shown in FIG. 2, a user taps on a touch screen 200which causes an application executing on the UE 102, or an operatingsystem component of the UE 102, to select a new MSISDN to be enabled.Regardless of the mechanism by which the change is initiated, the UE 102sends a message (or causes a message to be sent) to request that adifferent MSISDN be enabled, such as enabling IMSI2 (shown in FIG. 2with a circled “1”). The MDB 110 updates portion 112 to reflect thatMSISDN2 is enabled. The proxy 108 receives an indication of a change toenable one MSISDN and to disable another MSISDN. In the exampleillustrated in FIG. 2, this change is communicated to the proxy 108(shown with a circled “2”). The proxy 108 may periodically poll the MDB110 for changes, the MDB 110 may push changes to the proxy 108, or thechange may be communicated in some other way.

The proxy 108 updates the MSC/VLR 104 based on the indication of thechange in the enabled MSISDN. The proxy 108 transmits a new MAP ISDprofile message for MSISDN2 to the MSC/VLR 104 updating the MSC/VLR 104with the new subscriber information, including the now enabled MSISDN2(shown with a circled “3”). In this way, the proxy 108 causes theMSC/VLR 104 to associate IMSI1 with MSISDN2 (in this example), and anoutbound call placed from the UE 102 may now be made using thesubscription associated with MSISDN2. The MSC/VLR 104 replies to the MAPISD profile message with a MAP ISD response message (shown with acircled “4” in FIG. 2). In this interaction, the proxy 108 emulates anHLR, such as the HLR 106.

The proxy 108 causes a message to be sent to the UE 102 indicating thatthe change to enable MSISDN2 is completed. In the example shown in FIG.2, the proxy 108 transmits a “done” message to the MDB 110 (shown with acircled “5”) and the MDB 110 transmits a “done” message to the UE 102(shown with a circled “6”). However, in other embodiments, the changemay be communicated to the UE 102 in some other way, such as directlyfrom the proxy 108 to the UE 102, through some other intermediary, or insome other way.

FIG. 3 illustrates a network 100 and a process for incoming callhandling for a call to a currently enabled MSISDN. When a call comes in,a gateway MSC 300 requests routing information for the MSISDN. In theexample shown in FIG. 3, the gateway MSC 300 sends a send routinginformation (SRI) message to the HLR 106 (shown in FIG. 3 with a circled“1”). The SRI message specifies the MSISDN that is being called, forexample MSISDN2. The HLR 106 associates the MSISDN being called with theproxy 108, due to previous registration of an IMSI (such as IMSI2)associated with the MSISDN being called during the registration process,such as is illustrated in FIG. 1. The HLR 106 therefore sends a provideroaming number (PRN) message to the proxy 108 (shown with a circled “2”in FIG. 3). The proxy 108 receives this request to provide routinginformation for the incoming call associated with the MSISDN. As withother communications between the HLR 106 and the proxy 108, the proxy108 emulates a MSC/VLR in its communication with the HLR 106.

The proxy 108 determines whether the MSISDN being called is currentlyenabled for calling. The proxy 108 may maintain the active and enabledMSISDNs for UE 102 (and other UEs), such as in working memory or someother local memory, which may enable faster retrieval than performing alook-up to the MDB 110. For example, in the registration processillustrated in FIG. 1, the proxy 108 learns of the currently enabledMSISDN when the UE 102 registers with the MSC/VLR 104. In the exampleillustrated in FIG. 2, the proxy 108 learns of the currently enabledMSISDN when the currently enabled MSISDN is changed. If for some reasonthe proxy 108 does not know what MSISDN is currently enabled, it mayperform a look-up to the MDB 110 (shown in FIG. 3 with a dashed line).The proxy 108 may, in some embodiments, perform a look-up to the MDB 110every time a call comes in.

Where the MSISDN being called is currently enabled (as in FIG. 3), theproxy 108 transmits a request for the routing information to the MSC/VLR104. In the example shown in FIG. 3, the proxy 108 sends the PRN(provide roaming number) message to the MSC/VLR 104 (shown in FIG. 3with a circled “3”). The MSC/VLR 104 responds to the PRN message with aMSRN (shown in FIG. 3 with a circled “4”). The proxy 108 receives thisrouting information. As noted above, the MSRN is a temporary numbermapped to the MSISDN for a period of time, and is used for call routingpurposes. The MSC/VLR 104 stores the MSRN temporarily. As with othercommunications between the proxy 108 and the MSC/VLR 104, the proxy 108emulates an HLR in these communications.

The proxy 108 allocates its own MSRN which it then maps to the MSRNreceived from the MSC and transmits the routing information to the HLR106. In the example shown in FIG. 3, the proxy 108 transmits the MSRN tothe HLR 106 (shown in FIG. 3 with a circled “5”). The HLR 106 sends theMSRN to the gateway MSC 300 as a reply to the SRI message (shown in FIG.3 with a circled “6”). To establish the call, the gateway MSC 300 sendsa SIP INVITE to the MSRN which would subsequently be routed to the proxy108 (shown with a circled “7” in FIG. 3). In this communication, theproxy 108 emulates a MSC/VLR to the gateway MSC 300. The proxy 108 mapsthe MSRN back to the MSRN originally allocated by the MSC and sends aSIP INVITE to the MSC's MSRN which subsequently gets routed to theMSC/VLR 104 (shown with a circled “8”) in FIG. 3. Alternatively, thecall might be set up through a Signaling System No. 7 (SS7) networkusing an ISDN User Part (ISUP) Initial address message (IAM) to placethe call. Also, the network operator could elect to not have the Proxymap the MSRN to its own to interwork the call and simply forward theMSRN sent by the MSC to the HLR. In this case the call would be routedto the MSC/VLR 104 that the MSRN came from, and would not traverse theproxy. The MSC/VLR 104 then sets up the call with the UE 102.

FIG. 4 illustrates a network 100 and a process for incoming callhandling with dynamic update of MSISDN association. In the exampleillustrated in FIG. 3, the MSISDN being called is currently enabled forcalling. In the example illustrated in FIG. 4, the MSISDN being calledis not currently enabled. When a call comes in, a gateway MSC 300requests routing information for the MSISDN by transmitting a sendrouting information (SRI) message to the HLR 106 (shown in FIG. 4 with acircled “1”). The SRI message specifies the MSISDN that is being called,for example MSISDN2. The HLR 106 associates the MSISDN being called withthe proxy 108, due to previous registration of the IMSI associated withthe MSISDN being called during the registration process, such as isillustrated in FIG. 1. The HLR 106 sends a provide roaming number (PRN)message to the proxy 108 (shown with a circled “2” in FIG. 4). The proxy108 receives this request for routing information for the MSISDN. Aswith other communications between the HLR 106 and the proxy 108, theproxy 108 emulates a MSC/VLR in its communication with the HLR 106.

The proxy 108 determines whether the MSISDN being called is currentlyenabled for calling. The proxy 108 may maintain the active and enabledMSISDNs for UE 102 (and other UEs), such as in working memory or someother memory as discussed above with respect to FIG. 3. For example, inthe registration process illustrated in FIG. 1, the proxy 108 learns ofthe currently enabled MSISDN when the UE 102 registers with the MSC/VLR104. In the example illustrated in FIG. 2, the proxy 108 learns of thecurrently enabled MSISDN when the currently enabled MSISDN is changed.If for some reason the proxy 108 does not know what MSISDN is currentlyenabled, it may perform a look-up to the MDB 110. The proxy 108 may, insome embodiments, perform a look-up to the MDB 110 every time a callcomes in.

When a call comes in for a MSISDN that is not currently enabled forcalling (as in FIG. 4), the proxy 108 takes one or more steps to changethe MSISDN that is enabled before the call is completed. The proxy 108updates the MDB 110 to change the MSISDN that is enabled (shown in FIG.4 as a circled “3”). The proxy 108 also causes a message to be sent tothe UE 102 to indicate the change to enable MSISDN2 for calling (shownin FIG. 4 as a circled “4”). Updating the UE 102 may not be performed,and the call may be completed without updating the UE 102. Further tocause a change in the MSISDN that is enabled, the proxy 108 sends a MAPISD message for MSISDN2 to the MSC/VLR 104 (shown with a circled “5” inFIG. 4) to update the MSC/VLR 104 with the subscriber information,including the called MSISDN2 that is now currently enabled. The proxy108 thereby causes the MSC/VLR 104 to associate the IMSI stored on theUE 102 with the newly enabled MSISDN that is being called. In theexample illustrated in FIG. 4, the MSC/VLR 104 updates its associationsto associate IMSI1 with MSISDN2. In this communication, the proxy 108emulates the HLR 106.

The proxy 108 transmits a request for the routing information to theMSC/VLR 104. In the example shown in FIG. 4, the proxy 108 sends a PRNmessage for the now-enabled MSISDN2 to the MSC/VLR 104 (shown in FIG. 4with a circled “6”). The MSC/VLR 104 replies with a MSRN message (shownwith a circled “7” in FIG. 4) with a MSRN that it associated temporarilywith MSISDN2. The proxy 108 receives this routing information. In thiscommunication, the proxy 108 emulates the HLR 106.

The proxy 108 transmits the routing information to the HLR 106. In theexample shown in FIG. 4, the proxy 108 transmits a PRN Response messagewith the MSRN to the HLR 106 (shown with a circled “8”) in FIG. 4. Inthis communication, the proxy 108 emulates the MSC/VLR 104. The HLR 106sends a PRN Response message with the MSRN to the gateway MSC 300 (shownwith a circled “9” in FIG. 4). To establish the call, the gateway MSC300 sends a SIP INVITE to the MSRN which would subsequently be routed tothe proxy 108 (shown with a circled “10” in FIG. 4). In thiscommunication, the proxy 108 emulates a MSC/VLR to the gateway MSC 300.The proxy 108 maps the MSRN back to the MSRN originally allocated by theMSC and sends a SIP INVITE to the MSC's MSRN which subsequently getsrouted to the MSC/VLR 104 (shown with a circled “11”) in FIG. 4.Alternatively, the call might be set up through a Signaling System No. 7(SS7) network using an ISDN User Part (ISUP) Initial address message(IAM) to place the call. Also, the network operator could elect to nothave the Proxy map the MSRN to its own to interwork the call and simplyforward the MSRN sent by the MSC to the HLR. In this case the call wouldbe routed to the MSC/VLR 104 that the MSRN came from, and would nottraverse the proxy. The MSC/VLR 104 then sets up the call with the UE102.

In the embodiments illustrated in FIGS. 1-4, the proxy 108 is a separatehardware network component that emulates various other devices in thenetwork 100. In one or more alternative embodiments, the functionalityof the proxy 108 may be incorporated into the HLR 106. In theseembodiments, the HLR 106 causes the MSC/VLR 104 to associate the enabledMSISDN with the IMSI on the UE 102. The HLR updates the MDB 110 and/orthe UE 102 when a call comes in on a non-enabled MSISDN, and so forth.The MDB 110 is shown as a separate component in FIGS. 1-4, as well, butin one or more embodiments, the MDB 110 is incorporated into the proxy108 and/or the HLR 106. Other examples are possible without departingfrom the scope of embodiments.

The processes described above in association with FIGS. 1-4 can beimplemented in hardware, software, or a combination thereof. In thecontext of software, the operations represent computer-executableinstructions stored on one or more computer-readable storage media that,when executed by one or more processors, perform the recited operations.Generally, computer-executable instructions include routines, programs,objects, components, data structures, and the like that performparticular functions or implement particular abstract data types. Inother embodiments, hardware components perform one or more of theoperations. Such hardware components may include or be incorporated intoprocessors, application-specific integrated circuits (ASICs),programmable circuits such as field programmable gate arrays (FPGAs), orin other ways. The order in which the operations are described is notintended to be construed as a limitation, and any number of thedescribed operations can be combined in any order and/or in parallel toimplement the processes.

FIG. 5 illustrates an example network device 500 configured to performdynamic MSISDN association. As illustrated in FIG. 5, the network device500 includes processor(s) 502 and memory 504. A proxy module 506 isexecutable by the processor(s) 502 to perform various functions that arethe same as or similar to the proxy 108 described in FIGS. 1-4. Forexample, the proxy module 506 is configured, among other things, toemulate an HLR when communicating with a MSC/VLR, to emulate an MSC/VLRwhen communicating with an HLR, to cause an MSC/VLR to associate acurrently enabled MSISDN with an IMSI associated with a UE, and soforth.

As noted above, the proxy 108 and the HLR 106 depicted in FIGS. 1-4 maybe incorporated into a single computing system. The HLR module 508performs the functions of an HLR, such as the HLR 106. Similarly, thenetwork device 500 may include the MDB 110. The network device 500 alsoincludes interface(s) 510 that enable the network device 500 tocommunicate with other devices in a network, such as in a GSM network.Routing/switching hardware 512 provides routing and switchingfunctionality, such as SS7 routing and switching capabilities, or other.The interface(s) 510 and/or the routing/switching hardware may includeor be incorporated into processors, application-specific integratedcircuits (ASICs), programmable circuits such as field programmable gatearrays (FPGAs), or in other ways.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described. Rather,the specific features and acts are disclosed as exemplary forms ofimplementing the claims.

What is claimed is:
 1. A method of facilitating a multi-line mobileservice, the method comprising: storing, in a network database:information associating international mobile subscriber identities(IMSIs) with Mobile Station International Subscriber Directory Numbers(MSISDNs), and information indicating whether the MSISDNs are active andwhether the MSISDNs are enabled, wherein an indication in the networkdatabase that a particular MSISDN is active indicates that theparticular MSISDN is available to potentially be used for inbound andoutbound calls at a device with an associated IMSI, and wherein anindication in the network database that the particular MSISDN is enabledindicates that the particular MSISDN is set as the MSISDN to use forinbound and outbound calls at the device with the associated IMSI;receiving, by a network proxy from a mobile network switch, a locationupdate message that includes an IMSI of a mobile device that isregistered with the mobile network switch; determining, by the networkproxy, a plurality of MSISDNs associated with the mobile device bylooking up the IMSI in the network database, wherein the plurality ofMSISDNs includes at least a first MSISDN that is active and enabled, anda second MSISDN that is active but not enabled; transmitting, by thenetwork proxy to the mobile network switch in response to the locationupdate message, first subscriber data for the first MSISDN that isenabled; and refraining from transmitting, by the network proxy to themobile network switch in response to the location update message, secondsubscriber data for the second MSISDN that is not enabled.
 2. The methodof claim 1, wherein the IMSI is a first IMSI, and the method furthercomprises transmitting, from the network proxy to a home locationregister, based on receipt of the location update message: a firstlocation update message associated with the first MSISDN and the firstIMSI; and a second location update message associated with the secondMSISDN and a second IMSI associated with the second MSISDN.
 3. Themethod of claim 2, further comprising receiving, at the network proxyfrom the home location register, the first subscriber data for the firstMSISDN that is enabled and the second subscriber data for the secondMSISDN that is not enabled.
 4. The method of claim 1, furthercomprising: receiving, at the network proxy, indication of a change toenable the second MSISDN and to disable the first MSISDN; and based onthe indication, transmitting the second subscriber data from the networkproxy to the mobile network switch, the second subscriber dataassociating the IMSI with at least the second MSISDN.
 5. The method ofclaim 1, further comprising: receiving, at the network proxy from anetwork entity, a request to provide routing information for an incomingcall associated with the first MSISDN; transmitting, from the networkproxy to the mobile network switch, the request or another request toprovide the routing information for the incoming call associated withthe first MSISDN; receiving, at the network proxy from the mobilenetwork switch, the routing information for the incoming call; andtransmitting the routing information for the incoming call from thenetwork proxy to the network entity.
 6. The method of claim 5, whereinthe network entity is a home location register.
 7. The method of claim1, further comprising: receiving, at the network proxy from a networkentity, a request to provide routing information for an incoming callassociated with the second MSISDN that is not enabled; causing, based atleast on the request, the second MSISDN to be enabled and the firstMSISDN to be disabled; and transmitting the routing information for theincoming call from the network proxy to the network entity.
 8. Themethod of claim 7, wherein causing the second MSISDN to be enabledincludes transmitting the second subscriber data for the second MSISDNfrom the network proxy to the mobile network switch, the secondsubscriber data associating the second IMSI with the second MSISDN. 9.The method of claim 7, wherein causing the second MSISDN to be enabledand the first MSISDN to be disabled includes causing a message to betransmitted to the mobile device indicating that the second MSISDN is tobe set at the mobile device as the MSISDN to use for inbound andoutbound calls and that the first MSISDN is to be set at the mobiledevice not to be used for inbound or outbound calls.
 10. Atelecommunications network component, comprising: one or moreprocessors; memory; and one or more programming modules stored on thememory and executable by the one or more processors to: receive alocation update message from a visiting location register (VLR) of amobile switching center (MSC), the location update message indicatingthat a mobile device associated with an international mobile subscriberidentity (IMSI) is registered with the MSC; determine, based on alook-up to a database, a plurality of Mobile Station InternationalSubscriber Directory Numbers (MSISDNs) associated with the mobiledevice, including a first MSISDN that is active and enabled and a secondMSISDN that is active but not enabled; and based at least on the firstMSISDN being enabled and the second MSISDN being not enabled, causesubscriber data associated with the first MSISDN and not the secondMSISDN to be associated with the IMSI within the MSC, wherein an MSISDNbeing active indicates that the MSISDN is available to potentially beused for inbound and outbound calls at a device with an associated IMSI,and wherein the MSISDN being enabled indicates that the MSISDN is set asthe MSISDN to use for inbound and outbound calls at the device with theassociated IMSI.
 11. The telecommunications network component of claim10, wherein the subscriber data is first subscriber data associated withthe first MSISDN, and wherein the one or more programming modules arefurther executable by the one or more processors to: receive anindication of a change to enable the second MSISDN; and responsive tothe indication, cause second subscriber data associated with the secondMSISDN to be associated with the IMSI within the MSC.
 12. Thetelecommunications network component of claim 10, wherein the one ormore programming modules are further executable by the one or moreprocessors to: receive from a network entity a provide routing number(PRN) message for the first MSISDN; determine that the first MSISDN isenabled; cause the PRN message or another PRN message to be transmittedto the MSC; receive a mobile station routing number (MSRN) from the MSC;and reply to the PRN message by providing the MSRN to the networkentity.
 13. The telecommunications network component of claim 10,wherein the one or more programming modules are further executable bythe one or more processors to: receive from a network entity a providerouting number (PRN) message for the second MSISDN that is not enabled;and responsive to the PRN message, cause the second MSISDN to beenabled.
 14. The telecommunications network component of claim 13,wherein the one or more programming modules are further executable bythe one or more processors to: cause the PRN message or another PRNmessage to be transmitted to the MSC; receive a mobile station routingnumber (MSRN) from the MSC; and reply to the PRN message by providingthe MSRN.
 15. The telecommunications network component of claim 13,where in the subscriber data is first subscriber data associated withthe first MSISDN, and wherein the one or more programming modules arefurther executable by the one or more processors to cause the secondMSISDN to be enabled by at least causing second subscriber dataassociated with the second MSISDN to be associated with the IMSI withinthe MSC.
 16. A system comprising: a network database configured to storeinformation associating a plurality of Mobile Station InternationalSubscriber Directory Numbers (MSISDNs) with a mobile device that isassociated with an international mobile subscriber identity (IMSI), thenetwork database further configured to store indications of whetherindividual ones of the plurality of MSISDNs are active and whether theindividual ones of the plurality of MSISDNs are enabled, wherein anindication that a particular MSISDN is active indicates that theparticular MSISDN is available to potentially be used for inbound andoutbound calls at a device with an associated IMSI, and wherein anindication that the particular MSISDN is enabled indicates that theparticular MSISDN is set as the MSISDN to use for inbound and outboundcalls at the device with the associated IMSI; and a hardware networkcomponent configured to: receive, from a mobile switching center (MSC),a location update message indicating that the mobile device hasregistered with the MSC; determine from the network database a firstMSISDN and a second MSISDN associated with the IMSI, the first MSISDNbeing active and enabled, and the second MSISDN being active but notenabled; and based at least on the first MSISDN being enabled and thesecond MSISDN being not enabled, cause the MSC to associate the firstMSISDN with the IMSI.
 17. The system of claim 16, wherein the hardwarenetwork component is further configured to: receive a message indicatingthat the second is enabled; and based at least on the message, cause theMSC to associate the second MSISDN with the IMSI.
 18. The system ofclaim 16, wherein the hardware network component is further configuredto: receive a message that an incoming call is directed towards thefirst MSISDN that is enabled; and cause, responsive to the message, arouting number for the incoming call to be provided to a switchingnetwork.
 19. The system of claim 16, wherein the hardware networkcomponent is further configured to: receive a message that an incomingcall is directed towards the second MSISDN that is not enabled; based atleast on the message, cause the MSC to associate the second MSISDN withthe IMSI; and cause, responsive to the message, a routing number for theincoming call to be provided to a switching network.
 20. The system ofclaim 19, wherein the hardware network component is further configuredto, based at least on the message, cause a second message to betransmitted to the mobile device indicating a change from the firstMSISDN being enabled to the second MSISDN being enabled.